This invention relates to a card reader and to a card for use with the card reader.
A known card reader for, for example, a bank cash withdrawal terminal works on the principle of magnetic induction in a dynamic mode. The card has a ferric oxide strip which, as the card is inserted into the mouth of the card reader, is guided past a magnetic head, similar to a magnetic tape recorder head, and the head and associated circuitry reads the personal code recorded in the ferric oxide strip. This enables the terminal to dispense the cash and debit by the appropriate amount the account of that person, to whom the personal code was allocated.
With the advent of viewdata systems such as the British Post Office PRESTEL System it will be necessary for the computer to recognise to whom the charge for use of the system is to be billed. For some purposes it might be satisfactory for the terminal itself to be given an integral personal code and to bill a certain person as a consequence of the use of that particular terminal. Clearly however such an arrangement has drawbacks, the main one being that where such a terminal is shared amongst a number of users it is not possible for the computer to bill the various users separately. Another drawback arises through fraudulent or unauthorised use of the terminal which, once again, runs up a bill against one person, usually the owner or lessee, but not the user.
Hence a better solution would be to equip each terminal with a card reader and provide each prospective user of the viewdata system with his own personal card so that the pertaining personal account will be debited each time the terminal is used.